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    <title>Document</title>

        <style>

            /* not( 否定选择器 */

            li:not(:first-child){
                background-color: aqua;
            }

        </style>

</head>
<body>
    <ul>

        <li>111111</li>
        <li>222222</li>
        <li>333333333</li>

    </ul>
</body>
</html>